The most probable diagnosis for the patient in question is atrioventricular nodal re-entrant tachycardia (AVNRT).The presenting features of the patient are suggestive of supraventricular tachycardia (SVT). The most common form of SVT in children over 8 years old is atrioventricular nodal re-entrant tachycardia. It occurs as a result of an additional electrical circuit in or near the AV node itself.Other options:- Atrial Flutter: is a form of re-entry tachycardia within the atria which then becomes unsynchronised with the ventricles, which is not the case here. Furthermore, it is most common in babies and children with congenital heart disease.- Atrial tachycardia: is a condition where an area of atrium takes over the pacemaker activity of the heart. However, it is relatively uncommon.- Atrioventricular re-entrant tachycardia (AVRT): occurs due to an accessory electrical pathway between the atria and ventricles forming a re-entry circuit. This is the most common cause of SVT in children < 8 years old. One of the specific diagnoses of AVRT is Wolff-Parkinson-White syndrome. However, WPW syndrome is much rarer than AVNRT.- Premature atrial contractions (PACs): are very common in normal, healthy children and adolescents. Occasionally, they can give rise to the feeling of a 'skipped beat'. Fortunately, they are rarely associated with any significant underlying pathology or need to be treated.

Answer: Inflammatory bowel diseaseThe inflammatory bowel diseases (IBDs), including ulcerative colitis and Crohn disease, are chronic inflammatory disorders of the gastrointestinal tract most often diagnosed in adolescence and young adulthood, with a rising incidence in paediatric populations. Inflammatory bowel disease is caused by a dysregulated mucosal immune response to the intestinal microflora in genetically predisposed hosts. Although children can present with the classic symptoms of weight loss, abdominal pain, and bloody diarrhoea, many present with nonclassical symptoms of isolated poor growth, anaemia, or other extraintestinal manifestations.Colorectal Carcinoma (CRC) is rare in patients less than 20 years of age.

Administration of IV prostaglandin/PGE1 (e.g., alprostadil) is indicated in ductal-dependent CHDs until surgery can be performedMechanism: prostaglandin prevents the ductus arteriosus from closing → creates intentional shunt to allow mixing of deoxygenated with oxygenated blood.

Congenital adrenal hyperplasia is a common cause of virilisation in females that can present as ambiguous genitalia at birth. Deficiency of the 21-alphahydroxylase enzyme is implicated in excess mineralocorticoid and androgens produced by the adrenal gland. Virilisation occurs when excess androgens are converted to testosterone in a genetically female foetus, causing the genitalia to resemble male genitalia. A deficiency of 5-alpha hydroxylase would rather decrease the production of testosterone and lead to the presentation of external female genitalia in a genetically male foetus. Autoantibodies against glutamic acid are seen in type 1 diabetes mellitus, while defects in the AIRE gene and the FOXP3 affect components of the immune system.

The cells in the testes that secrete testosterone are the Leydig cells.Other cells in testes include:- Spermatogonia: These are undifferentiated male germ cells which undergo spermatogenesis in the seminiferous tubules of the testes.- Sertoli cells: They are a part of the seminiferous tubule of the testes, cells are activated by FSH and nourish developing sperm cells.- Myoid: They are squamous contractile cells which generate peristaltic waves, they surround the basement membrane of testes.- Fibroblasts: Cells which synthesise collagen and the extracellular matrix.

The presentation is suggestive of nephrotic syndrome. A trial of corticosteroids is the first step in treatment of idiopathic nephrotic syndrome. Diuretics are useful in managing symptomatic oedema. Cyclosporin and cyclophosphamide are indicated in frequently relapsing and steroid dependant disease.

The age of the patient and the presence of immature white blood cells are suggestive of leukaemia. Hodgkin’s disease is unlikely in this age group and it usually presents with lymphadenopathy. In HIV, immature white blood cells are not present in the blood.

Meckel’s diverticulum is a congenital diverticulum of the small intestine. It is a remnant of the omphalomesenteric duct (also called the vitellointestinal duct) and contains ectopic ileal, gastric or pancreatic mucosa.Rule of 2’s- occurs in 2% of the population- it is located 2 feet proximal to the ileocaecal valve- it is 2 inches long- it is 2 times more common in men- there are 2 tissue types involvedIt is typically asymptomatic. Symptomatic presentation indicates inflammation of the diverticulum. The symptoms include:- Abdominal pain mimicking appendicitis- Rectal bleeding- Intestinal obstruction: secondary to an omphalomesenteric band (most commonly), volvulus and intussusceptionManagement:Surgical removal if the neck of the diverticulum is narrow or symptomatic. Surgical options are excision or formal small bowel resection and anastomosis.

Pale, bulky, malodorous stools are evidence of fat malabsorption syndrome. The diagnostic test is jejunal biopsy to rule out other differential diagnoses such as celiac disease, giardiasis or Crohn’s disease etc.

This is probably a case of protein-induced allergic proctitis, due to dietary protein transmitted through the mother to the breast-fed child. The mother should go on a milk-free and soya-free diet but continue to breast-feed.

Key Observations:

1. Cyanosis and Low Oxygen Saturation:
   • Central cyanosis indicates mixing of oxygenated and deoxygenated blood.
   • The aortic oxygen saturation is low (76%), indicating a significant amount of deoxygenated blood entering systemic circulation.
2. Pressure Analysis:
   • The right ventricle pressure is significantly elevated (110/6 mmHg), suggesting an obstructive lesion like pulmonary stenosis or an increased volume load due to a shunt.
   • The pulmonary artery pressure is low (20/5 mmHg) despite the high right ventricular pressure, suggesting an obstruction to flow from the right ventricle to the pulmonary artery, consistent with pulmonary stenosis.
3. Oxygen Saturation Analysis:
   • There is a notable drop in oxygen saturation from the left ventricle (87%) to the aorta (76%), indicating a mixture of oxygenated and deoxygenated blood in the systemic circulation, suggestive of a right-to-left shunt.

Differential Diagnosis:

1. Pulmonary Stenosis:
   • Supported by elevated right ventricular pressure and low pulmonary artery pressure.
2. Ventricular Septal Defect (VSD):
   • Would typically cause left-to-right shunting, leading to increased pulmonary blood flow and higher oxygen saturation in the right ventricle and pulmonary artery, which is not observed here.
3. Over-riding Aorta:
   • Seen in conditions like Tetralogy of Fallot where the aorta receives blood from both the right and left ventricles, leading to mixed oxygen saturation.
4. Right-to-Left Shunt:
   • The data indicates a right-to-left shunt, with low oxygen saturation in the aorta, suggesting that deoxygenated blood is bypassing the lungs and entering systemic circulation.
5. Aortic Stenosis:
   • Typically presents with high left ventricular pressure and a pressure gradient between the left ventricle and the aorta, which is not observed here.

Conclusion:

Given the data, the most likely abnormalities present in this patient are Pulmonary Stenosis, Right-to-Left Shunt, and Over-riding Aorta. These findings are consistent with a condition like Tetralogy of Fallot, where all these features are present.

Oligomenorrhoea and BMI of 40.4 is suggestive of Polycystic ovary syndrome (PCOS). To diagnose PCOS 2 out of following 3 criteria should be present : oligo/anovulation, hyperandrogenism, clinical (hirsutism or less commonly male pattern alopecia) or biochemical (raised FAI or free testosterone) and polycystic ovaries on ultrasound.

Usage of inhaled corticosteroids are less associated with systemic adverse effects. However they are associated with local complications including dental caries and most commonly dysphonia.

The most probable diagnosis for this boy is primary hypothyroidism.Rationale:The development of secondary sexual characteristics in a boy aged less than 9 years of age is highly suggestive of precocious puberty.Around 80% of boys with precocious puberty have pathological causes and require detailed investigation. In this case, the child has long-standing short stature but coupled with the early puberty and delay in bone age, the diagnosis is primary hypothyroidism, which is the only cause of this clinical picture.

Hirsutism is the growth of excess hair in androgen dependent areas or in a male pattern. The phenomenon is found in conditions where there is abnormal androgen action. This can occur in adrenal lesions including congenital adrenal hyperplasia, and Cushing syndrome, or a failure to produce adequate female hormones such as PCOS and premature menopause. Similarly, drugs such as anabolic steroids, danazol and minoxidil can also cause hirsutism. Delayed puberty is unlikely to cause hirsutism.

This patient has Wilson’s disease. They Kayser-Fleischer ring (ring that encircles the iris) is diagnostic of this. Low serum copper is seen in Wilson’s disease. With the Kayser-Fleischer ring, this makes all of the other answer choices incorrect.

The most common congenital cyanotic heart disease and the most common cause of blue baby syndrome, Tetralogy of Fallot shows four cardiac malformations occurring together. These are ventricular septal defect (VSD), pulmonary stenosis (right ventricular outflow obstruction), overriding aorta (degree of which is variable), and right ventricular hypertrophy. The primary determinant of severity of disease is the degree of pulmonary stenosis. Tetralogy of Fallot is seen in 3-6 per 10,000 births and is responsible for 5-7% congenital heart defects, with slightly higher incidence in males. It has also been associated with chromosome 22 deletions and DiGeorge syndrome. It gives rise to right-to-left shunt leading to poor oxygenation of blood. Primary symptom is low oxygen saturation in the blood with or without cyanosis at birth of within first year of life. Affected children ay develop acute severe cyanosis or ‘tet spells’ (sudden, marked increase in cyanosis, with syncope, and may result in hypoxic brain injury and death). Other symptoms include heart murmur, failure to gain weight, poor development, clubbing, dyspnoea on exertion and polycythaemia. Chest X-ray reveals characteristic coeur-en-sabot (boot-shaped) appearance of the heart. Treatment consists of immediate care for cyanotic spells and Blalock–Taussig shunt (BT shunt) followed by corrective surgery.

Lesch-Nyhan syndrome is a condition that occurs almost exclusively in males. This condition is inherited in an X-linked recessive pattern It is characterized by neurological and behavioural abnormalities and the overproduction of uric acid. Uric acid is a waste product of normal chemical processes and is found in blood and urine. Excess uric acid can be released from the blood and build up under the skin and cause gouty arthritis (arthritis caused by an accumulation of uric acid in the joints). Uric acid accumulation can also cause kidney and bladder stones.The nervous system and behavioural disturbances experienced by people with Lesch-Nyhan syndrome include abnormal involuntary muscle movements, such as tensing of various muscles (dystonia), jerking movements (chorea), and flailing of the limbs (ballismus). People with Lesch-Nyhan syndrome usually cannot walk, require assistance sitting, and generally use a wheelchair. Self-injury (including biting and head banging) is the most common and distinctive behavioural problem in individuals with Lesch-Nyhan syndrome.

Topical benzoyl peroxide is used for the treatment of mild to moderate acne vulgaris. It is actually a peeling agent and it clears the pores and reduces the bacterial cell count.

The prognosis for croup is excellent, and recovery is almost always complete with complications being quite rare. The possible complications are pneumonia, bacterial tracheitis, pulmonary oedema, pneumothorax, pneumomediastinum, lymphadenitis or otitis media. Bacterial tracheitis is a life-threatening infection that can arise after the onset of an acute viral respiratory infection.

A preterm with respiratory distress syndrome presents with the condition as a result of immature lungs and inadequate surfactant production. Management of RDS therefore includes surfactant therapy, oxygen administration and mechanical ventilation, as well as measures such maintaining acid base levels and blood haemoglobin in an intensive care unit. Dexamethasone is not shown to be particularly effective when given to a preterm, but can however be used to prevent or decrease RDS severity when given to the mother before delivery.

Transfusion with blood products carries a risk of acute and more chronic adverse reactions. These reactions can either be immune mediated due to a component mismatch, or non immune, underpinned by bacterial or viral contamination. Reactions range from very mild such as urticaria, to life threatening in the case of transfusion-related acute lung injury. In transfusion with packed red blood cells, the most common adverse event is pyrexia, while urticaria is the most common adverse event that follows infusion with FFP.

By the age of 3 months Jasmine should startle to loud noises, recognise her parents voices and turn to them when they are speaking, and should quiet down or smile at the sound of a familiar voice when crying. She should also cry when she is uncomfortable or irritated. By the time Jasmine is 9 months old she would begin to understand and respond to the word ‘no’ as well as other easy commands. She would be able vocalise and babble with repetitive sounds, and imitate adults’ playful sounds. She would be much less likely startled by loud noises.

Henoch–Schönlein purpura (HSP), also known as IgA vasculitis, is a disease of the skin, mucous membranes, and sometimes other organs that most commonly affects children. In the skin, the disease causes palpable purpura (small, raised areas of bleeding underneath the skin), often with joint pain and abdominal pain. It is an acute immunoglobulin A (IgA)–mediated disorder. The tetrad of purpura, arthritis, kidney inflammation, and abdominal pain is often observed.

Cranial nerves I, II, and VIII are considered purely afferent nerves since they conduct sensory information from the olfactory region, the retina of the eye, and the inner ear structures, respectively.Cranial nerves III, IV, VI, XI, and XII are considered purely efferent due to their motor output to the orbit, the neck, and the tongue.Cranial nerves V, VII, IX, and X are considered mixed cranial nerves due to the presence of afferent and efferent fibres with both sensory and motor components.

This patient in question is most likely suffering from inflammatory bowel disease, probably ulcerative colitis. The most valuable investigation that can assess the severity and extent of the disease, including the opportunity to obtain biopsies is a colonoscopy.Other options:Barium studies and abdominal x-rays do not give sufficient information. While they can provide indicative evidence, only a colonoscopy-guided biopsy can confirm IBD.Radio-isotope scans will help in identifying a focus such as a Meckel’s diverticulum, and angiography is rarely indicated unless a vascular lesion is suspected of causing the intestinal bleed.

Atopic dermatitis is an allergic condition which is more apparent in those children who have a positive family history in their 1st or 2nd degree relatives. In some cases, there might be a positive history of bronchial asthma. The best treatment option in this case would be topical application of 1% hydrocortisone ointment to the affected areas of the child. We cannot prescribe a strong ointment to the face because it may lead to skin atrophy, telangiectasia and other steroid related topical complications.

The heart is the first organ to form and become functional, emphasizing the importance of transport of material to and from the developing infant. It originates about day 18 or 19 from the mesoderm and begins beating and pumping blood about day 21 or 22. It forms from the cardiogenic region near the head and is visible as a prominent heart bulge on the surface of the embryo. Originally, it consists of a pair of strands called cardiogenic cords that quickly form a hollow lumen and are referred to as endocardial tubes. These then fuse into a single heart tube and differentiate into the truncus arteriosus, bulbus cordis, primitive ventricle, primitive atrium, and sinus venosus, starting about day 22. The primitive heart begins to form an S shape within the pericardium between days 23 and 28. The internal septa begin to form about day 28, separating the heart into the atria and ventricles, although the foramen ovale persists until shortly after birth. Between weeks five and eight, the atrioventricular valves form. The semilunar valves form between weeks five and nine.

Based on the studies, genetic factors are responsible for approximately 60 % DVT cases. Factor V (FV) Leiden which is the most common cause of inherited thrombophilia, predisposes patients to DVT because of resistance to protein C.The heritable causes of deep vein thrombosis, from most to least common are:Factor V LeidenProthrombin G20210A variantProtein C deficiencyProtein S deficiencyAntithrombin deficiencyVon Willebrand disease and thalassaemia are not causes of DVT.

Among the given options, pituitary adenoma is an acquired anterior pituitary disorder which represent between 10 and 25% of all intracranial neoplasms.Other options:- Agenesis of the corpus callosum is characterised by the partial or complete absence of the corpus callosum. This condition is associated with pituitary hormone deficiencies.- Congenital disorders such as hydrocephalus or arachnoid cysts may be a cause of precocious puberty.- Pituitary hypoplasia and septo-optic dysplasia are congenital disorders of the pituitary gland.

The external aspect of the tympanic membrane is lined by stratified squamous epithelium. Clinical correlation: Following middle ear infections, this type of epithelium can migrate into the middle ear through a perforated tympanic membrane.The ear is composed of three anatomically distinct regions: – External ear: Auricle is composed of elastic cartilage covered by skin. The lobule has no cartilage and contains fat and fibrous tissue. External auditory meatus is variable in length, measuring approximately 2.5cm long in fully grown children. Lateral third of the external auditory meatus is cartilaginous, and the medial two-thirds is bony. The greater auricular nerve innervates the region. The auriculotemporal branch of the trigeminal nerve supplies most of the external auditory meatus and the lateral surface of the auricle. – Middle ear: It is the space between the tympanic membrane and cochlea. The aditus leads to the mastoid air cells is the route through which middle ear infections may cause mastoiditis. Anteriorly the eustachian tube connects the middle ear to the nasopharynx. The tympanic membrane consists of an outer layer of stratified squamous epithelium, a middle layer of fibrous tissue and an inner layer of mucous membrane continuous with the middle ear. The chorda tympani nerve passes on the medial side of the pars flaccida. The glossopharyngeal nerve and pain innervate the middle ear. Thus, pain may radiate to the middle ear following tonsillectomy. – Ossicles:Malleus attaches to the tympanic membrane (the Umbo). Malleus articulates with the incus (synovial joint). Incus attaches to stapes (another synovial joint). – Internal ear:It consists of the cochlea, semicircular canals, and vestibule. Organ of Corti is the sense organ of hearing and is located on the inside of the cochlear duct on the basilar membrane. Vestibule accommodates the utricle and the saccule. These structures contain endolymph and are surrounded by perilymph within the vestibule. The semicircular canals lie at various angles to the petrous temporal bone. All share a common opening into the vestibule.

The patient’s history points to absence seizures. Carbamazepine has been shown to aggravate generalized seizure types, especially absence seizures, because it acts directly on the ventrobasal complex of the thalamus which is critical to the neurophysiology of absence seizures.

A patient with Down’s syndrome is likely to be subfertile rather than infertile.Down’s syndrome:The clinical features of Down’s syndrome include:- Face: upslanting palpebral fissures, epicanthic folds, Brushfield spots in iris, protruding tongue, small ears, and round/flat face- Flat occiput- Single palmar crease, pronounced ‘sandal gap’ in the first interdigital space of the feet.- Hypotonia- Congenital heart defects (40-50%)- Duodenal atresia- Hirschsprung’s diseaseThe cardiac complications in these patients include:- Endocardial cushion defect (40%)- Ventricular septal defect (30%)- Secundum atrial septal defect (10%)- Tetralogy of Fallot (5%)- Isolated patent ductus arteriosus (5%)The complications that occur later in the life of the patient include:- Subfertility: Males are almost always infertile due to impaired spermatogenesis. Females, however, are usually subfertile and have an increased incidence of problems with pregnancy and labour.- Learning difficulties- Short stature- Repeated respiratory infections (+hearing impairment from glue ear)- Acute lymphoblastic leukaemia- Hypothyroidism- Alzheimer’s disease- Atlantoaxial instability

A teratoma is a tumour containing tissue elements that are similar to normal derivatives of more than one germ layer. They usually contain skin, hair, teeth and bone tissue and are more common in children, behaving as a benign tumour. After puberty, they are regarded as malignant and can metastasise.

Congenital TB symptoms typically develop during the second or third week of life and include poor feeding, poor weight gain, cough, lethargy, and irritability. Other symptoms include fever, ear discharge, and skin lesions.Signs of congenital TB include failure to thrive, icterus, hepatosplenomegaly, tachypnoea, and lymphadenopathy.

Based on the clinical presentation, the pubic hair development is in Tanner stage 2.The Tanner stages for pubic hair are as follows:Stage 1 – pre-adolescentStage 2 – sparse hair that is long, slightly pigmented and downyStage 3 – hair spread over the junction of the pubes, darker and coarserStage 4 – adult-type hair, but the area covered is smaller than it is in an adult.Stage 5 – adult in quantity and type

Insufficient surfactant production in premature infants leads to respiratory distress syndrome or surfactant deficient lung disease (SDLD), characterized by structurally immature lungs. There are many risk factors of this disease, some of them include male gender, caesarean section, infants of diabetic mothers, being the second born of the premature twins, perinatal asphyxia, sepsis, and hypothermia. Maternal hypertension is not a recognized risk factor for respiratory distress syndrome| instead, pregnancy-induced hypertension and chronic maternal hypertension are the protective factors against this disease.

A micturating cystourethrogram (MCUG) is one type of imaging test also called a voiding cystourethrogram (VCUG). The MCUG can check whether the flow of urine from the child’s bladder is being blocked, or whether it goes up the wrong way. It can help diagnose certain conditions, including vesicoureteral reflux and posterior urethral valves.

Children are able to use a palmar grasp by the age of 6 months and use a pincer grasp by the age of 9 to 10 months. They can sit with support by 6 months and sit without support by 7 to 9 months. They can vocalize by 3 months. Stranger fear appears from 7 to 10 months. So this baby’s development is normal.

Based on the clinical scenario, the most probable diagnosis for this patient is maxillary sinusitis.The maxillary sinus drains from its superior aspect, leaving it prone to infections. It is the most commonly affected sinus in sinusitis.Common symptoms of maxillary sinusitis include postnasal discharge, pain, headache and toothache.Radiological imaging may show a fluid level in the antrum.Common organisms causing maxillary sinusitis include Haemophilus influenzae or Streptococcus pneumoniae.Treatment with antral lavage may facilitate diagnosis and relieve symptoms. Antimicrobial therapy has to be continued for long periods. Antrostomy may be needed.Other options:- Frontal sinusitis more commonly causes intracranial complications, but it is still less frequent than maxillary sinusitis.- The petrosal sinus is not a cavity within bone| rather, it is a venous structure located beneath the brain.- Frontoethmoidal sinusitis: It usually presents with frontal headache, nasal obstruction and altered sense of smell. Inflammation may progress to involve periorbital tissues. Ocular symptoms may occur, and secondary CNS involvement brought about by infection entering via emissary veins. CT scanning is the imaging modality of choice. Early cases may be managed with antibiotics. More severe cases usually require surgical drainage.

Positive Kernig’s and Brudzinski’s signs may indicate meningitis. While awaiting blood culture results, a broad-spectrum antibiotic such as Cefotaxime (a third generation cephalosporin) is preferred over the other medications listed.

People who are at risk for severe illness and complications from measles, such as infants younger than 12 months of age, pregnant women without evidence of measles immunity, and people with severely compromised immune systems, should receive immunoglobulin. Intramuscular immunoglobulin should be given to all infants younger than 12 months of age who have been exposed to measles. For infants aged 6 through 11 months, MMR vaccine can be given in place of IG, if administered within 72 hours of exposure.

Hereditary diseases follow specific inheritance patterns according to the type of gene involved. Mutations in the genes which are on the sex chromosome, chromosome X are called X-linked diseases. X-linked recessive conditions result when both the copies of X-chromosomes are defective, which happens in the case of females since males have only one X- chromosome. Thus, these conditions are more common among males, and examples include colour blindness, haemophilia, Lesch-Nyhan syndrome, and hunter’s syndrome, etc. Hunter’s syndrome is a type of lysosomal storage disease which is also known as mucopolysaccharidosis II. Vitamin D resistant rickets is a X-linked dominant disease. Neurofibromatosis type 1 and 2 are autosomal dominant conditions while Wilson’s disease is autosomal recessive.

Milestones of 3 years old:Social and Emotional:Copies adults and friends Shows affection for friends without prompting Takes turns in games Shows concern for crying friend Understands the idea of “mine” and “his” or “hers” Shows a wide range of emotions Separates easily from mom and dad May get upset with major changes in routineDresses and undresses self Language/Communication:Follows instructions with 2 or 3 steps Can name most familiar things Understands words like “in,” “on,” and “under” Says first name, age, and sexNames a friend Says words like “I,” “me,” “we,” and “you” and some plurals (cars, dogs, cats) Talks well enough for strangers to understand most of the time Carries on a conversation using 2 to 3 sentences Cognitive (learning, thinking, problem-solving):Can work toys with buttons, levers, and moving parts Plays make-believe with dolls, animals, and people Does puzzles with 3 or 4 pieces Understands what “two” means Copies a circle with pencil or crayon Turns book pages one at a time Builds towers of more than 6 blocks Screws and unscrews jar lids or turns door handle Movement/Physical Development:Climbs well Runs easily Pedals a tricycle (3-wheel bike) Walks up and down stairs, one foot on each step

Diabetes insipidus (DI) is defined as the passage of large volumes (>3 L/24 hr) of dilute urine (< 300 mOsm/kg). It has the following 2 major forms:Central (neurogenic, pituitary, or neurohypophyseal) DI, characterized by decreased secretion of antidiuretic hormone (ADH| also referred to as arginine vasopressin [AVP])Nephrogenic DI, characterized by decreased ability to concentrate urine because of resistance to ADH action in the kidney.The boy most probably has nephrogenic diabetes insidious (DI) not central DI so he is not responding to the ADH treatment.

Narcolepsy is a rare condition characterised by excessive daytime sleepiness, sleep paralysis, hypnagogic hallucinations, and cataplexy (sudden collapse triggered by emotion such as laughing or crying). There is no cure for narcolepsy. Treatment options include stimulants, such as methylphenidate (Ritalin) or modafinil (Provigil), antidepressants, such as fluoxetine (Prozac), citalopram (Celexa), paroxetine (Paxil), sertraline (Zoloft) and sodium oxybate (Xyrem). Modafinil has replaced methylphenidate and amphetamine as the first-line treatment of excessive daytime sleepiness (EDS).

Vaccines should not be given to a feverish child.

Observational studies fall under the category of analytic study designs and are further sub-classified as observational or experimental study designs. The goal of analytic studies is to identify and evaluate causes or risk factors of diseases or health-related events. The differentiating characteristic between observational and experimental study designs is that in the latter, the presence or absence of undergoing an intervention defines the groups. By contrast, in an observational study, the investigator does not intervene and rather simply “observes” and assesses the strength of the relationship between an exposure and disease variable.Three types of observational studies include cohort studies, case-control studies, and cross-sectional studies. Case-control and cohort studies offer specific advantages by measuring disease occurrence and its association with an exposure by offering a temporal dimension (i.e. prospective or retrospective study design). Cross-sectional studies, also known as prevalence studies, examine the data on disease and exposure at one particular time point. Because the temporal relationship between disease occurrence and exposure cannot be established, cross-sectional studies cannot assess the cause and effect relationshipDisadvantage of Cohort study is Susceptible to selection bias.

The spinal cord ends at L3 in the new-bornmigrates cephalad during childhood to end at L1 – L2 and reaches adult size by the age of 10.

The rational part of a teen’s brain isn’t fully developed until the age of 25 or so.In fact, recent research has found that adult and teen brains work differently. Adults think with the prefrontal cortex, the brain’s rational part. This is the part of the brain that responds to situations with good judgment and an awareness of long-term consequences. Teens process information with the amygdala. This is the emotional part.